Carved into the belly of a mountain, Fordo is considered impregnable to airstrikes and most bunker-buster
bombs.

Two top Iranian officials – Deputy Head of the Iranian Atomic Energy Agency Seyyed Shamseddin Barbroudi and chairman of the Iranian parliament’s Committee for Foreign Policy and National Security Alaeddin Boroujerdi, dismissed the reports of the blast – carried by American news website WMD – and referred to them as "Western-made propaganda."

According to the Times, while WND could not supply any independent corroboration for the report, an Israeli defense official allegedly said that "We're still trying to understand exactly what happened… We don't know if this was sabotage or an accident."

The newspaper further quotes Home Front Defense Minister Avi Dichter
as saying: "Any explosion in Iran that doesn’t hurt people but hurts its assets is welcome."

Prior to denying reports of the explosion Iran had initially called it "an act of sabotage."

In December, Iran claimed it had uncovered a monitoring device disguised as a rock near the underground nuclear enrichment plant.

Western intelligence sources said that the

"fake rock" exploded when Revolutionary Guards who were on a patrol in the area tried to move it.